Shuttle Payload Flight Test Article, originally scheduled for launch on STS-16, but ultimately brought forward to STS-8 due to payload delays. It was an aluminum structure resembling two wheels with a six-meter long central axle, ballasted with lead to give it a total mass of 3,855 kg (8,499 lb), which could be lifted by the shuttle's Canadarm robot arm to give astronauts experience in using the system. It was stored in the midsection of the payload bay.
Status: Operational 1983. First Launch: 1983-08-30. Last Launch: 1983-08-30. Number: 1 . Gross mass: 3,855 kg (8,498 lb). Apogee: 223 km (138 mi).